Shin was one of 179 survivors rescued before the ferry became totally submerged.

Some 475 passengers and crew were on the vessel when it suddenly listed and sank into the sea early Wednesday, many of them teenagers a field trip. Eighteen people are confirmed dead and 278 remain missing.

As water rushed into the passenger cabins, many on board were trapped and unable to escape.

In a series of desperate messages to her father, 16-year-old Kim Woong-Ki sent a text describing the unfolding crisis on the ship, according to Korean media.

“It’s dangerous if I move,” she said.

“I know that the rescue is going on but if it’s possible just come out,” her father replied.

“Dad, the ferry has tilted too much. I cannot walk, there’s too many of us in the corridor and it’s too tilted.”

There was no further communication, and Kim was listed among the hundreds still unaccounted for, AFP reported.

At a news conference early Thursday, the coast guard official in charge of the rescue operations was asked about reports that relatives had received mobile phone messages from missing passengers since the ferry sank under the surface.

Kim Soo-hyun, chief of the western regional coast guard, said officials were aware investigating the reports but said the timing of the messages could not immediately be verified.